Exposure to environmental chemicals can perturb an individual's metabolic set point, especially during critical periods of development, and as a result increase his or her propensity towards obesity that is manifested later in life and possibly in successive generations. We hypothesized that benzyl butyl phthalate (BBP), a widespread endocrine disruptor, may impair one important epigenetic regulator, sirtuin, in mesenchymal stem cells and induce adipogenesis. Our results showed that gene expression of two well-known adipogenic markers, aP2 and PPARγ, were significantly increased from day 2 to day 8 under 50μM BBP exposure when compared to control in C3H10T1/2 stem cells (p<0...

Eukaryotic cells maintain protein homeostasis through the activity of multiple basal and inducible systems, which function in concert to allow cells to adapt to a wide range of environmental conditions. Whilst the transcriptional programs regulating individual pathways have been studied in detail, it is not known how the different pathways are transcriptionally integrated such that a deficiency in one pathway can be compensated by a change in an auxiliary response. One such pathway that plays an essential role in many proteostasis responses is the ubiquitin-proteasome system (UPS), which functions to degrade damaged, unfolded or short half-life proteins...

A maternal high-fat (HF) diet during pregnancy can lead to metabolic compromise, such as insulin resistance in adult offspring. Skeletal muscle mitochondrial dysfunction is one mechanism contributing to metabolic impairments in insulin resistant states. Therefore, the present study aimed to investigate whether mitochondrial dysfunction is evident in metabolically compromised offspring born to HF-fed dams. Sprague-Dawley dams were randomly assigned to receive a purified control diet (CD; 10% kcal from fat) or a high fat diet (HFD; 45% kcal from fat) for 10 days prior to mating, throughout pregnancy and during lactation...

Methamphetamine (MA) produces long-lasting deficits in dopaminergic neurons in the long-term use via several neurotoxic mechanisms. The effects of MA on mitochondrial biogenesis is less studied currently. So, we evaluated the effects of repeated escalating MA regimen on transcriptional factors involved in mitochondrial biogenesis and glial-derived neurotrophic factor (GDNF) expression in substantia nigra (SN) and striatum of rat. In male wistar rats, increasing doses of MA (1-14 mg/kg) were administrated twice a day for 14 days...

Apelin, an endogenous ligand of the G-protein-coupled receptor APJ, is a novel myokine and may play a key role in regulating energy metabolism. The purpose of the present study was to investigate the effects of hypoxic exposure, exercise, and hypoxic exercise training on the expression of apelin and APJ in skeletal muscle of obese mice. 60 two-month old C57BL/6J mice were randomly divided into two groups: 10 in normal diet group (N) and 50 in the high fat diet (HFD) groups. After two months of feeding, the HFD mice whose body weight 20% higher than the average weight of N group were selected as obese mice and were further allocated into four groups: Control (C), Exercise (E), Hypoxia (H), and Exercise plus Hypoxia (E+H), at 8-9 mice/group...

The aim of the present study was to evaluate the therapeutic effect of the novel neuroprotective multitarget brain permeable monoamine oxidase inhibitor/iron chelating-radical scavenging drug, VAR10303 (VAR), co-administered with high-calorie/energy-supplemented diet (ced) in SOD1(G93A) transgenic amyotrophic lateral sclerosis (ALS) mice. Administration of VAR-ced was initiated after the appearance of disease symptoms (at day 88), as this regimen is comparable with the earliest time at which drug therapy could start in ALS patients...

Epidemiological studies show that sulfur dioxide (SO2), a major air pollutant, is associated with the morbidity and mortality of respiratory tract diseases. The aim of the present study was to determine the effects of SO2 on mitochondria and the corresponding molecular characterization in the lung. Male Wistar rats were exposed to 0, 3.5, 7, and 14 mg/m(3) SO2 (4 h/day, 30 days). Mitochondrial dysfunction including decreases of cytochrome c oxidase (COX) activity and mitochondrial membrane potential (MMP) was observed in the lungs of rats after SO2 inhalation...

Ectotherms often respond to prolonged cold exposure by increasing mitochondrial capacity via elevated mitochondrial volume density [V V(mit,f)]. In fish, higher V V(mit,f) is typically associated with increased expression of nuclear respiratory factor 1 (Nrf1), a transcription factor that induces expression of nuclear-encoded respiratory genes. To examine if nrf1 expression or the expression of other genes that regulate mitochondrial biogenesis contribute to changes in whole-organism metabolic rate during cold acclimation, we examined the time course of changes in the expression of these genes and in metabolic rate in Atlantic killifish, Fundulus heteroclitus...

Cytochrome-c-oxidase (COX) deficiency is a frequent cause of mitochondrial disease and is associated with a wide spectrum of clinical phenotypes. We studied mitochondrial function and biogenesis in fibroblasts derived from the Cohen (CDs) rat, an animal model of COX deficiency. COX activity in CDs-fibroblasts was 50% reduced compared to control rat fibroblasts (P<0.01). ROS-production in CDs fibroblasts increased, along with marked mitochondrial fragmentation and decreased mitochondrial membrane-potential, indicating mitochondrial dysfunction...

Previous work indicated that lysine-specific demethylase 1 (Lsd1) can positively regulate the oxidative and thermogenic capacities of white and beige adipocytes. Here we investigate the role of Lsd1 in brown adipose tissue (BAT) and find that BAT-selective Lsd1 ablation induces a shift from oxidative to glycolytic metabolism. This shift is associated with downregulation of BAT-specific and upregulation of white adipose tissue (WAT)-selective gene expression. This results in the accumulation of di- and triacylglycerides and culminates in a profound whitening of BAT in aged Lsd1-deficient mice...

Overactive mitochondrial fission was shown to promote cell transformation and tumor growth. It remains elusive how mitochondrial quality is regulated in such conditions. Here, we show that upregulation of mitochondrial fission protein, dynamin related protein-1 (Drp1), was accompanied with increased mitochondrial biogenesis markers (PGC1α, NRF1, and Tfam) in breast cancer cells. However, mitochondrial number was reduced, which was associated with lower mitochondrial oxidative capacity in breast cancer cells...

PURPOSE: This study assessed the mitochondrial related signaling responses to a single bout of non-contact, modified football (touch rugby), played as small-sided games (SSG), or cycling (CYC) exercise in sedentary, obese, middle-aged men. METHOD: In a randomized, cross-over design, nine middle-aged, sedentary, obese men completed two, 40-min exercise conditions (CYC and SSG) separated by a 21-d recovery period. Heart rate (HR) and Ratings of Perceived Exertion were collected during each bout...

Molecular mediators of metabolic processes, to increase energy expenditure, have become a focus for therapies of obesity. The discovery of cytokines secreted from the skeletal muscle (SKM), termed "myokines," has garnered attention due to their positive effects on metabolic processes. Interleukin-15 (IL-15) is a myokine that has numerous positive metabolic effects and is linked to the PPAR family of mitochondrial regulators. Here, we aimed to determine the importance of PPARα and/or PPARδ as targets of IL-15 signaling...

Nrf1 and Nrf2 (NF-E2-related factors 1 and 2, respectively) are transcription factors that belong to the Cap'n'collar (CNC) family and play critical roles in various tissues, including the liver. Liver-specific Nrf1 knockout mice show hepatic steatosis, accompanied by dysregulation of various metabolic genes. Nrf2 knockout mice show impairment in the induction of antioxidant and xenobiotic-metabolizing enzyme genes. Although it has been shown that small Maf (sMaf) proteins act as obligatory partners of CNC proteins, their precise contributions to the function of CNC proteins remain unclear especially in the context of adult liver functions...

Development is a complex and well-defined process characterized by rapid cell proliferation and apoptosis. At this stage in life, a developmentally young organism is more sensitive to toxicants as compared to an adult. In response to pro-oxidant exposure, members of the Cap'n'Collar (CNC) basic leucine zipper (b-ZIP) transcription factor family (including Nfe2 and Nfe2-related factors, Nrfs) activate the expression of genes whose protein products contribute to reduced toxicity. Here, we studied the role of the CNC protein, Nfe2, in the developmental response to pro-oxidant exposure in the zebrafish (Danio rerio)...

The purpose of our study was to understand the protective effects of a partial reduction of dynamin-related protein 1 (Drp1) in Alzheimer's disease (AD) progression and pathogenesis. Increasing evidence suggests that phosphorylated Tau and mitochondrial abnormalities are involved in the loss of synapses, defective axonal transport and cognitive decline, in patients with AD. In the current study, we investigated whether a partial reduction of Drp1 protect neurons from phosphorylated Tau-induced mitochondrial and synaptic toxicities in AD progression...

KEAP1 is a substrate adaptor protein for a CUL3-based E3 ubiquitin ligase. Ubiquitylation and degradation of the antioxidant transcription factor NRF2 is considered the primary function of KEAP1; however, few other KEAP1 substrates have been identified. Because KEAP1 is altered in a number of human pathologies and has been proposed as a potential therapeutic target therein, we sought to better understand KEAP1 through systematic identification of its substrates. Toward this goal, we combined parallel affinity capture proteomics and candidate-based approaches...

BACKGROUND: Mitochondria are of major importance in oocyte and early embryo, playing a key role in maintaining energy homeostasis. Epidemiological findings indicate that maternal undernutrition-induced mitochondrial dysfunction during pregnancy is associated with the development of metabolic disorders in offspring. Here, we investigated the effects of moderately decreased maternal energy intake during pregnancy on skeletal muscle mitochondrial biogenesis in fetal offspring with pig as a model...